Higher zoom levels (up to e.g. 28)

[SomeoneElseOSM]

Would there ever be an appetite for optionally supporting zoom levels > 20? The changes to support it are here:

https://github.com/openstreetmap/mod_tile/compare/master...SomeoneElseOSM:mod_tile:zoom2022

although it's not something that it would make sense to turn on by default because the metatile path isn't compatible with existing metatiles, and many people wouldn't want to lose that cache.

I've been running a version of that code for 8 years or so and haven't really found any drawbacks, provided that the "tile dirtying after update" logic has sensible settings. Extra disk usage hasn't really been a problem; people tend on to zoom in that far and pan around.